[BASH] read 'line' issue with leading tabs and virtual line breaks Post: 302943417

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Top Forums Shell Programming and Scripting [BASH] read 'line' issue with leading tabs and virtual line breaks Post 302943417 by sea on Friday 8th of May 2015 07:19:06 AM

05-08-2015

Registered User

True, inside the script.
As far i can tell, there is no lasting effect for outside the script:

Code:

:) tmp $  ../prjs/tui/bin/tui-cat -d 0.01 sample.txt 
|| #                                                                                                              ||
|| #    Commment title                                                                                            ||
|| #                                                                                                              ||
||     Idented text                                                                                               ||
||     [ -z "$EMPTY" ] && \                                                                                       ||
||         echo "yes $EMPTY is empty!"                                                                            ||
|| --hmm                                                                                                          ||
||     ident again                                                                                                ||
||                                                                                                                ||
+ tmp $ echo ":$IFS:"
: 	
:

Seems right'ish to me.

EDIT:
I used a single IFS="" for both modes, cat and typewriter (the example above, -d 0.001 is the delay with each char (text only, not borders) is shown.
But changing anyway, for better practice, thank you for pointing out.

Last edited by sea; 05-08-2015 at 08:27 AM..

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cat

CAT(1)                                                             User Commands                                                            CAT(1)

NAME

       cat - concatenate files and print on the standard output

SYNOPSIS

       cat [OPTION]... [FILE]...

DESCRIPTION

       Concatenate FILE(s) to standard output.

       With no FILE, or when FILE is -, read standard input.

       -A, --show-all
              equivalent to -vET

       -b, --number-nonblank
              number nonempty output lines, overrides -n

       -e     equivalent to -vE

       -E, --show-ends
              display $ at end of each line

       -n, --number
              number all output lines

       -s, --squeeze-blank
              suppress repeated empty output lines

       -t     equivalent to -vT

       -T, --show-tabs
              display TAB characters as ^I

       -u     (ignored)

       -v, --show-nonprinting
              use ^ and M- notation, except for LFD and TAB

       --help display this help and exit

       --version
              output version information and exit

EXAMPLES

       cat f - g
              Output f's contents, then standard input, then g's contents.

       cat    Copy standard input to standard output.

AUTHOR

       Written by Torbjorn Granlund and Richard M. Stallman.

REPORTING BUGS

       GNU coreutils online help: <http://www.gnu.org/software/coreutils/>
       Report cat translation bugs to <http://translationproject.org/team/>

COPYRIGHT

       Copyright (C) 2017 Free Software Foundation, Inc.  License GPLv3+: GNU GPL version 3 or later <http://gnu.org/licenses/gpl.html>.
       This is free software: you are free to change and redistribute it.  There is NO WARRANTY, to the extent permitted by law.

SEE ALSO

       tac(1)

       Full documentation at: <http://www.gnu.org/software/coreutils/cat>
       or available locally via: info '(coreutils) cat invocation'

GNU coreutils 8.28                                                 January 2018                                                             CAT(1)